thumb|Portuguese Socialist Party leader [[Azedo Gneco speaking at a May 1 meeting, 1907]]The Portuguese Socialist Party () was a Portuguese political party.
History
The party was founded in 1875. During its initial phase, it was heavily influenced by Proudhonism and rejected revolutionary Marxism. In 1919 the leftwing of the party broke away (that group would merge with anarcho-syndicalists to form the Portuguese Maximalist Federation, which became the Portuguese Communist Party). The Socialist Party lacked mass support. The trade union movement was led by anarchists and was not affiliated with the socialist International Federation of Trade Unions.
The party won two seats in the parliamentary elections of 1911, 1912, 1915 and 1925.
The party was a member of the Labour and Socialist International between March 1925 and 1933.